The present invention relates to an object position estimating system, and an object position estimating apparatus, an object position estimating method and an object position estimating program used for such a system that estimate a position of an object located within an environment based upon data observed by an observation unit, for example, in the order of earlier observation time.
In an attempt to estimate an ID and a position of a target object within an environment by identifying the target object that is present in the environment by the use of a sensor such as a camera, an operation, mainly classified into five processes, are required.
In the first process, the target object is photographed by a camera so that image data including the target object is obtained.
In the second process, by comparing the image data including the target object with a template of a background image preliminarily held, a differential image is obtained.
In the third process, by using a database in which pixel positions in the preliminarily held image data and positions within the environment are associated with one another, positional candidates of the object within the environment of the obtained differential image are obtained.
In the fourth process, by using a database in which IDs of objects preliminarily held and image data are made associated with each other, ID candidates of the object corresponding to the resulting differential image are obtained. Hereinafter, the third process (process in which positional candidates of the object are obtained) and the fourth process (process in which ID candidates of the object are obtained) are combinedly referred to as an “object identifying” process.
In the fifth process, since the date of the ID candidate and position candidate of individual objects have uncertainty, the most likely position of each of the objects is estimated by using data relating to the ID and position of the object previously obtained by a camera. The fifth process is hereinafter referred to as “position estimating” process.
It is necessary to carry out an object identifying process by which data obtained by allowing the sensor to observe the environment are converted to data relating to the ID candidates and positional candidates of the object that can be handled by the object position estimating process.
A period of time required for the position estimation (the fifth process) is longer than a period of time (from the first process to the fourth process) required for the observation of the environment by the sensor and the completion of the object identifying process. Therefore, in the case where each of data after the object identifying process is individually subjected to a position estimating process with respect to all the target objects located inside the environment, there is a delay time (waiting time for response) between a point of time when the sensor observes the environment and a point of time when the object identifying process is completed. FIG. 13 shows an example thereof. It is the time 14:17′:20″ (14 o'clock:17 minutes:20 seconds) when observation data 1 of the observation device 1 is subjected to the object identifying process so that the object position estimating process can be carried out. It is the time 14:17′:26″ when the observation data 2 of the observation device 2 is subjected to the object identifying process so that the object position estimating process can be carried out. However, at the point of time, 14:17′:26″, the object position estimating process of the observation data 1 has not been completed, with the result that the time when the object position estimating process of the observation data 2 can be started is from the time 14:17′:30″ when the object position estimating process of the observation data 1 has been completed. Consequently, there is a waiting period of time until the object position estimating process of the observation data 1 has been completed, before the object position estimating process of the observation data 2 is started.
As a method for reducing the waiting period of time for response from such a device or the like, for example, Patent Document 1 has disclosed a technique in which, a probability of abnormal response is found by statistically processing communication states or communication apparatus states collected up to the present time, the probability data of the abnormal response is found, and a time-out period of time is determined based upon the probability data of the abnormal response.